The present invention relates to a latching device for use on a vehicle and, more particularly, to a latching device provided with a locking mechanism and a safety mechanism capable of acting by inertia to prevent the locking mechanism being undone when the vehicle collide against an obstacle.
A conventional latching device of for such a use comprises a casing having an opening, a latching member supported for sliding in the casing so as to be inserted in and removed from the casing through the opening, urging means for urging the latching member so that the latching member projects from the casing, and a locking mechanism which locks the latching member at a locking position within the casing against the urging force of the urging means and capable of being undone when the latching member is pushed to an unlocking position within the casing. Such a latching device is disclosed in, for example, Japanese Utility Model Laid-open (Kokai) Nos. Sho 60-11977, Sho 61-163870, Sho 61-176373, Sho 63-199140 and Hei 1-163682.
Storing devices for vehicles, provided with a safety mechanism capable of preventing a locking mechanism being undone by inertia are disclosed in, for example, Japanese Patent Laid-open (Kokai) No. Sho 64-41434 and Japanese Utility Model Laid-open (Kokai) No. Hei 2-25332.
Two types of known safety mechanisms have been used in combination with different locking mechanisms, respectively.
The locking mechanism for the former storing device disclosed in Japanese Patent Laid-open (Kokai) No. Sho 64-41434 employs a grooved cam provided with a heart-shaped cam groove, and a locking lever controlled by the grooved cam. A safety mechanism combined with this locking mechanism comprises a movable member that is able to be moved into the range of turning motion of the locking lever by inertia, and spring means for urging the movable member outside the range of turning motion of the locking lever.
The locking mechanism for the latter storing device disclosed in Japanese Utility Model Laid-open No. Hei 2-25332 employs a hook member, and a locking pin that engages the hook member. A safety mechanism combined with this locking mechanism comprises a movable member capable of being moved into the range of turning motion of the hook member by inertia, and spring means urging the movable member outside the range of turning motion of the hook member.
However, it is difficult to miniaturize a latching device incorporating the conventional safety mechanism.
The safety mechanism disclosed in Japanese Patent Laid-open (Kokai) No. Sho 64-41434 needs to dispose the movable member beside the locking lever, which increases the width of the latching device.
Since the cam groove of the locking mechanism extends under the pivot on which the locking lever turns, it is difficult to dispose the pivot and the locking mechanism has a complicated construction.
The locking mechanism disclosed in Japanese Utility Model Laid-open (Kokai) No. Hei 2-25332 is unsuitable for use in combination with a small latching device because the hook member must be turned through a comparatively large angle.
Accordingly, it is an object of the present invention to provide a latching device of a simple construction having a reduced size, provided with a locking mechanism of a reduced size employing a locking lever pivotally supported on a movable member, and a grooved cam provided with a heart-shaped cam groove for controlling the locking lever.
A sliding movable member employed in both the foregoing known safety mechanisms needs a guide member having a guide surface for guiding the movable member for sliding movement, and frictional resistance opposing the relative motion between the movable member and the guide member is liable to impede the movement of the movable member.
Accordingly, another object of the present invention is to provide a latching device of a simple construction having a reduced size, employing a movable member pivotally supported within a casing so as to restrain a latching member directly from backward movement and to prevent damaging a locking mechanism, having high reliability, and capable of satisfactorily responding to inertial force.